A normal read operation (hereinafter, standard read) in a memory provides for supplying to the memory an address which identifies a corresponding location of the memory. After a specific time interval has elapsed, termed access time, the datum stored in said location is available at the output of the memory.
Memories are known in which, besides the standard reading operation, it is possible to carry out a page mode read operation which, in the case where only the less significant bits of the address supplied at the input of the memory vary, makes it possible to obtain valid data at the output of the memory in a shorter time than the standard access time.
Other known memories, however, in addition to the possibility of carrying out a standard read, have the possibility of carrying out a burst mode read. By supplying to the memory an external clock signal and an address corresponding to an initial memory location, the memory internally increments the address automatically and delivers at the output new data corresponding to the successive memory addresses at each cycle of the clock signal. This read mode makes it possible to reduce the access time significantly in all those cases where, instead of accessing memory locations distributed randomly in the memory space, it is necessary to access a certain number of contiguous memory locations.
Also known are electrically programmable and erasable non-volatile memories having a possibility of simultaneous operation in erasure or programming (more generally in the mode of modification of their content), and in read. This functional capability is obtained by means of subdivision of the memory into two independent banks, such that while in one of the two memory banks a programming or erasure operation is carried out in the background, it is possible to carry out a simultaneous read operation in the other memory bank. The read is however a standard type read, therefore does not benefit from the possibilities of a reduction in the access time offered by the two particular read modes described previously. Rapid access to the memory with a burst mode read or page mode read is permitted only on completion of the background programming or erasure of the other bank, or, in memories which provide it, by temporarily suspending the background operation.